Validation of Pediatric Index of Mortality-2 scoring system in a pediatric intensive care unit, Barbados

Predicting Clinical Deterioration and Mortality at Differing Stages During Hospitalization: A Systematic Review of Risk Prediction Models in Children in Low- and Middle-Income Countries

OBJECTIVE

To determine which risk prediction model best predicts clinical deterioration in children at different stages of hospital admission in low- and middle-income countries.

METHODS

For this systematic review, Embase and MEDLINE databases were searched, and Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. The key search terms were "development or validation study with risk-prediction model" AND "deterioration or mortality" AND "age 0-18 years" AND "hospital-setting: emergency department (ED), pediatric ward (PW), or pediatric intensive care unit (PICU)" AND "low- and middle-income countries." The Prediction Model Risk of Bias Assessment Tool was used by two independent authors. Forest plots were used to plot area under the curve according to hospital setting. Risk prediction models used in two or more studies were included in a meta-analysis.

RESULTS

We screened 9486 articles and selected 78 publications, including 67 unique predictive models comprising 1.5 million children. The best performing models individually were signs of inflammation in children that can kill (SICK) (ED), pediatric early warning signs resource limited settings (PEWS-RL) (PW), and Pediatric Index of Mortality (PIM) 3 as well as pediatric sequential organ failure assessment (pSOFA) (PICU). Best performing models after meta-analysis were SICK (ED), pSOFA and Pediatric Early Death Index for Africa (PEDIA)-immediate score (PW), and pediatric logistic organ dysfunction (PELOD) (PICU). There was a high risk of bias in all studies.

CONCLUSIONS

We identified risk prediction models that best estimate deterioration, although these risk prediction models are not routinely used in low- and middle-income countries. Future studies should focus on large scale external validation with strict methodological criteria of multiple risk prediction models as well as study the barriers in the way of implementation.

TRIAL REGISTRATION

PROSPERO International Prospective Register of Systematic Reviews: Prospero ID: CRD42021210489.

Performance and analysis of four pediatric mortality prediction scores among critically ill children: A multicenter prospective observational study in four PICUs

OBJECTIVE

We aimed to evaluate and compare the prognostic performance of common pediatric mortality scoring systems (the Pediatric Index of Mortality 2 [PIM2], PIM3, Pediatric Risk of Mortality [PRISM], and PRISM4 scores) to determine which is the most applicable score in our pediatric study cohort.

METHODS

This prospective observational multicenter cohort study was conducted in four tertiary-care pediatric intensive care units (PICUs) in Turkey. All children, between 1 month and 16 years old, admitted to the participating PICUs between October 1, 2019, and March 31, 2020, were included in the study. Discrimination between death and survival was assessed by area under the receiver operating characteristic plot (AUC) for each model. The Hosmer-Lemeshow goodness-of-fit (GOF) test was used to assess the calibration of the models, RESULTS: A total of 570 patients (median age 35 months) were enrolled in the study. The observed mortality rate was 8.2% (47/570). The standardized mortality ratio (SMR) of PIM2, PIM3, PRISM, and PRISM4 with 95% confidence interval (CI) were 0.94 (0.68-1.23), 1.27 (0.93-1.68), 0.86 (0.63-1.13), and 1.5 (1.10-1.97), respectively. The AUC with 95% CI was 0.934 (0.91-0.96) for PIM2, 0.934 (0.91-0.96) for PIM3, 0.917 (0.88-0.95) for PRISM, and 0.926 (0.88-0.97) for PRISM4 models. The Hosmer-Lemeshow test showed that the difference between observed and predicted mortality by PIM3 (p = 0.003) and PRISM4 (p = 0.008) was statistically significant whereas PIM2 (p = 0.28) and PRISM (p = 0.62) showed good calibration.

CONCLUSION

The overall performance of (both discrimination and calibration) PRISM and PIM2 scoring systems in Turkish pediatric patients aged 1 month to 16 years was accurate and had the best fit for risk groups according to our study. Although PIM3 and PRISM4 have good discriminatory power, their calibration was very poor in our study cohort.

Value of Thrombomodulin as a Marker for Sepsis in Critically Ill Children

OBJECTIVE

Pediatric sepsis is altered organ function in critically ill children and a main etiology of mortality for children. Therefore, the authors aimed to assess the role of serum thrombomodulin as valuable biomarker in the diagnosis and prognosis of sepsis in acutely ill pediatrics in the intensive unit.

METHODS

This prospective clinical study conducted on 140 acutely ill patients admitted to the Pediatric Intensive Care Unit (PICU) of Menoufia University Hospital and 50 apparently healthy controls from October 2018 through September 2019. All included children were subjected to clinical examination and the Pediatric Risk of Mortality (PRISM) and Pediatric Index of Mortality II (PIM II) scores were calculated. Serum thrombomodulin was measured for both patients and the control group upon admission. The children were followed for a period of 30 d.

RESULTS

Serum thrombomodulin level was increased among all the patients and those with systemic inflammatory response syndrome (SIRS), sepsis and severe sepsis compared with controls (p < 0.001). Furthermore, serum thrombomodulin was higher in patients who died than who survived (p = 0.005). Thrombomodulin had area under Receiver Operating Characteristic Curve (AUC) =0.915 for predicting sepsis, whereas C-reactive protein had AUC = 0.789. According to the prognosis, thrombomodulin had AUC = 0.711 for predicting mortality whereas PRISM and PIM scores had AUC = (0.918, 0.960) respectively.

CONCLUSIONS

Serum thrombomodulin is a promising marker for pediatric sepsis. The data showed that serum thrombomodulin had a valuable role in diagnosis of sepsis early in critically ill pediatrics.

Validity of Pediatric Index of Mortality 2 score as an Outcome Predictor in Pediatric ICU of a Public Sector Tertiary Care Hospital in Pakistan

Pediatric Index of Mortality 2 (PIM-2) is one of the leading mortality scores used in intensive care units all around the world. We assessed its validity as an outcome predictor in a pediatric intensive care unit (PICU) of Mayo Hospital/King Edward Medical University Lahore, Pakistan. We enrolled 154 consecutive admissions, aged 1 month to 13 years, requiring intensive care from January to June of 2019. Patient demographics along with PIM-2 data were collected; PIM-2 score and mortality risk was calculated; and the outcome recorded as death or survival. The median age at admission was 0.50 years (interquartile range [IQR]: 0.24–1.78) and the median weight was 5.0 kg (IQR: 3.08–10.0) with females constituting 54%; malnutrition was also common (66%). Observed mortality was 29.9% (46 out of 154) and expected mortality (cut-off ≥ 99.8%) was 27.9% with a standardized mortality ratio of 1.07 (95% confidence interval [CI]: 0.79–1.41). Sepsis was the most common diagnosis at admission (27.9%) with the highest mortality (52.2%). Chi-square analysis revealed a sensitivity of 54.3% and a specificity of 83.3% (p-value 0.00). PIM-2 score showed acceptable discrimination between survivors and nonsurvivors with an area under the receiver operating characteristic curve of 0.75 (95% CI: 0.67–0.84) (p-value = 0.00); however, poor calibration according to Hosmer–Lemeshow goodness of fit test (Chi-square = 15.80, df = 7, and p-value of 0.027 [< 0.1]), thus requiring recalibration according to local population characteristics.

Causes of death in critically ill paediatric patients in Japan: a retrospective multicentre cohort study

OBJECTIVES

The primary objective is to clarify the clinical profiles of paediatric patients who died in intensive care units (ICUs) or paediatric intensive care units (PICUs), and the secondary objective is to ascertain the demographic differences between patients who died with and without chronic conditions.

METHODS

In this retrospective multicentre cohort study, we collected data on paediatric death from the Japanese Registry of Pediatric Acute Care (JaRPAC) database. We included patients who were ≤16 years of age and had died in either a PICU or an ICU of a participating hospital between April 2014 and March 2017. The causes of death were compared between patients with and without chronic conditions.

RESULTS

Twenty-three hospitals participated, and 6199 paediatric patients who were registered in the JaRPAC database were included. During the study period, 126 (2.1%) patients died (children without chronic illness, n=33; children with chronic illness, n=93). Twenty-five paediatric patients died due to an extrinsic disease, and there was a significant difference in extrinsic diseases between the two groups (children without chronic illness, 15 (45%); children with chronic illness, 10 (11%); p<0.01). Cardiovascular disease was the most common chronic condition (27/83, 29%). Eighty-three patients (85%) in the chronic group died due to an intrinsic disease, primarily congenital heart disease (14/93, 15%), followed by sepsis (13/93, 14%).

CONCLUSIONS

The majority of deaths were in children with a chronic condition. The major causes of death in children without a chronic illness were due to intrinsic factors such as cardiovascular and neuromuscular diseases, and the proportion of deaths due to extrinsic causes was higher in children without chronic illness.

Comparison of Pediatric Risk of Mortality III, Pediatric Index of Mortality 2, and Pediatric Index of Mortality 3 in Predicting Mortality in a Pediatric Intensive Care Unit

Aims  To compare and validate the Pediatric Risk of Mortality (PRISM) III, Pediatric Index of Mortality (PIM) 2, and PIM 3 scores in a tertiary care pediatric intensive care unit (PICU) (Indian setting). Materials and Methods  All consecutively admitted patients in the PICU of a public hospital (excluding those with unstable vital signs or cardiopulmonary resuscitation within 2 hours of admission, cardiopulmonary resuscitation before admission, and discharge or death in less than 24 hours after admission) were included. PRISM III, PIM 2, and PIM 3 scores were calculated. Mortality discrimination for the three scores was calculated using the receiver operating characteristic (ROC) curve, and calibration was performed using the Hosmer-Lemeshow goodness-of-fit test. Results  A total of 350 patients were included (male:female = 1.3:1) over the study duration of 18 months (median age: 12 months [interquartile range: 4-60 months]). Nearly half were infants (47.4%). Patients with central nervous system disease were the highest (22.8%) followed by cardiovascular system (20.6%). Mortality rate was 39.4% (138 deaths). The area under the ROC curve for the PRISM III score was 0.667, and goodness-of-fit test showed no significant difference between the observed and expected mortalities in any of these categories ( p  > 0.5), showing good calibration. Areas under the ROC curve for the PIM 2 and PIM 3 scores were 0.728 and 0.726, respectively. For both the scores, the goodness-of-fit test showed good calibration. Conclusions  Although all the three scores demonstrate good calibration, the PIM 2 and PIM 3 scores have an advantage regarding the better discrimination ability, ease of data collection, simplicity of computation, and inherent capacity of not being affected by treatment in PICU.

Validation of the Pediatric Index of Mortality 3 in a Single Pediatric Intensive Care Unit in Korea

To compare mortality rate, the adjustment of case-mix variables is needed. The Pediatric Index of Mortality (PIM) 3 score is a widely used case-mix adjustment system of a pediatric intensive care unit (ICU), but there has been no validation study of it in Korea. We aim to validate the PIM3 in a Korean pediatric ICU, and extend the validation of the score from those aged 0-16 to 0-18 years, as patients aged 16-18 years are admitted to pediatric ICU in Korea. A retrospective cohort study of 1,710 patients was conducted in a tertiary pediatric ICU. To validate the score, the discriminatory power was assessed by calculating the area under the receiver-operating characteristic (ROC) curve, and calibration was evaluated by the Hosmer-Lemeshow goodness-of-fit (GOF) test. The observed mortality rate was 8.47%, and the predicted mortality rate was 6.57%. For patients aged < 18 years, the discrimination was acceptable (c-index = 0.76) and the calibration was good, with a χ² of 9.4 in the GOF test (P = 0.313). The observed mortality rate in the hemato-oncological subgroup was high (18.73%), as compared to the predicted mortality rate (7.13%), and the discrimination was unacceptable (c-index = 0.66). In conclusion, the PIM3 performed well in a Korean pediatric ICU. However, the application of the PIM3 to a hemato-oncological subgroup needs to be cautioned. Further studies on the performance of PIM3 in pediatric patients in adult ICUs and pediatric ICUs of primary and secondary hospitals are needed.

Pediatric Index of Mortality 2 as a predictor of death risk in children admitted to pediatric intensive care units in Latin America: A prospective, multicenter study

PURPOSE

The purpose of this study is to asses the performance of the Pediatric Index of Mortality 2 (PIM2) score in pediatric intensive care units (PICUs) in Latin America.

MATERIALS AND METHODS

This is a prospective, observational, multicenter study. We included patients aged 1 month to 16 years old admitted consecutively during 1 year to 34 PICUs in 9 Latin American countries. Discrimination and calibration tests were performed to validate the performance of PIM2 in the entire sample and in different subgroups.

RESULTS

A total of 7391 patients were analyzed. Pediatric Index of Mortality 2 predicted 573 deaths, whereas the observed deaths were 663 (P < .001). The area under the receiver operating characteristic curve for the entire population was 0.817 (95% confidence interval, 0.808-0.825). The score showed good discrimination. Instead, calibration was inadequate. The difference between observed and predicted deaths for the entire population and across different risk intervals was statistically significant (χ(2) = 121.87; df = 8; P < .001). Pediatric Index of Mortality 2 did not predict mortality correctly in different diagnostic categories (injury, postoperative, and miscellaneous), in children younger than 12 months, adolescents, and patients with chronic complex conditions.

CONCLUSIONS

Pediatric Index of Mortality 2 showed good discrimination, but calibration was inadequate. To use PIM2 for monitoring PICU performance in Latin America, it might be necessary to recalibrate the score locally.

Pediatric Index of Mortality and PIM2 scores have good calibration in a large cohort of children from a developing country

OBJECTIVE

Our objective was to validate the Pediatric Index of Mortality (PIM) and PIM2 scores in a large cohort of children from a developing country.

DESIGN

Prospective observational study.

SETTING

Pediatric intensive care unit of a tertiary care teaching hospital.

PATIENTS

All children aged <18 years admitted between June 2011 and July 2013.

MEASUREMENTS AND MAIN RESULTS

We evaluated the discriminative ability and calibration as measured by the area under the receiver operating characteristic (ROC) curves, the Hosmer-Lemeshow goodness-of-fit (GOF), and standardized mortality ratio (SMR), respectively. Of the 819 children enrolled, 232 (28%) died. The median (IQR) age of the study subjects was 4 years (0.8, 10). The major reasons for ICU admission as well as mortality were sepsis/severe sepsis. The area under ROC curves for PIM and PIM2 was 0.72 (95% CI: 0.67-0.75) and 0.74 (95% CI: 0.70-0.78), respectively. The goodness-of-fit test showed a good calibration across deciles of risk for the two scores with P values being >0.05. The SMR (95% CI) was 0.99 (0.85-1.15) and 1 (0.85-1.16) for PIM and PIM2, respectively. The calibration across different age and diagnostic subgroups was also good.

CONCLUSION

PIM and PIM2 scores had good calibration in our setup.

Critical Analysis of PIM2 Score Applicability in a Tertiary Care PICU in Western India

Objective. Children have limited physiological reserve that deteriorates rapidly. Present study profiled patients admitted to PICU and determined PIM2 score applicability in Indian setting. Patients and Methods. Prospective observational study. Results. In 742 consecutive admissions, male : female ratio was 1.5 : 1, 35.6% patients were ventilated, observed mortality was 7%, and 26.4% were <1 year. The profile included septicemia and septic shock (29.6%), anemia (27.1%), pneumonia (19.6%), and meningitis and encephalitis (17.2%). For the first year, sensitivity of PIM2 was 65.8% and specificity was 71% for cutoff value at 1.9 by ROC curve analysis. The area under the curve was 0.724 (95% CI: 0.69, 0.76). This cutoff was validated for second year data yielding similar sensitivity (70.6%) and specificity (65%). Logistic regression analysis (LRA) over entire data revealed various variables independently associated with mortality along with PIM2 score. Another logistic model with same input variables except PIM2 yielded the same significant variables with Nagelkerke R square of 0.388 and correct classification of 78.5 revealing contribution of PIM2 in predicting mortality is meager. Conclusion. Infectious diseases were the commonest cause of PICU admission and mortality. PIM2 scoring did not explain the outcome adequately, suggesting need for recalibration. Following PALS/GEM guidelines was associated with better outcome.

Application of pediatric index of mortality version 2: score in pediatric intensive care unit in an African developing country

Introduction

Outcome of patients admitted to PICU can be evaluated by many illness severity scoring systems. This prospective observational study evaluated the outcome of patients admitted to PICU in Fayoum University hospital of a developing country using the pediatric index of mortality version 2 scoring system.

Methods

All patients included in this study were subjected to data collection including demographics, diagnoses at admission, duration of ICU stay (DOS), pediatric index of mortality version 2 (PIM2) score and hospital outcome. The ratio of observed to predicted mortality (standardized mortality ratio (SMR)) was calculated for the set of patients.

Results

The study included 205 patients. The main causes of admission were respiratory, cardiovascular and neurological illnesses. Patients stay in ICU ranged from 1 - 45 days with a median 6 (interquartile range (IQ): 3-9) days. Discriminatory function of PIM2 scoring system was acceptable with the area under the ROC curve 0.76 (95%CI: 0.60-0.91). PIM2 calibrated well using Hosmer Lemeshow analysis (H-L X2= 1.410, df= 8, p=0.9). The mean predicted mortality was 5.6 (95% CI: 3.43 - 7.91) and the observed mortality was 8.8% giving a SMR 1.55.

Conclusion

PIM2 scoring system show adequate discriminatory function and well calibrated for the case mix of patients in PICU of Fayoum, Egypt. It can be used as beneficial tool for evaluation of risk adjusted mortality. Further larger scale studies in cooperation with other Egyptian universities and neighboring countries can improve the performance of our PICUs and critical care services.

Pediatric index of mortality 2 score as an outcome predictor in pediatric Intensive Care Unit in India

Background and Aims:

Pediatric index of mortality (PIM) 2 score is one of the severity scoring systems being used for predicting outcome of patients admitted to intensive care units (ICUs). The aim of the present study was to evaluate the usefulness of PIM2 score in predicting mortality in a tertiary care pediatric ICU (PICU) and to assess the associated factors in predicting mortality such as presence of shock, need for assisted ventilation and Glasgow coma scale <8.

Materials and Methods:

This was a prospective observation study done at tertiary care PICU from May 2011 to July 2011. Consecutive 119 patients admitted to PICU (aged 1 month to 12 years) were enrolled in the study. PIM2 scoring was done for all patients. The outcome was recorded as death or discharge. The associated factors for mortality were analyzed with SPSS 17.

Results:

PIM2 score discriminated between death and survival at a 99.8 cut-off, with area under receiver operating characteristic curve 0.843 with 95% confidence interval (CI) (0.765, 0.903). Most patients were referred late to this hospital, which explains higher death rate (46.2%), lesser length of hospital stay (mean 2.98 days) in the mortality group, and increased rate of mechanical ventilation (68.1%). Presence of shock was independently associated with mortality, as evidenced by binary logistic regression.

Conclusion:

PIM2 score discriminated well between survivors and death at PICU. Presence of shock was significantly associated with mortality.

Impact of severe sepsis on serum and urinary biomarkers of acute kidney injury in critically ill children: an observational study

BACKGROUND/AIMS

We hypothesized that sepsis could have an impact on the sensitivity of serum and urinary neutrophil gelatinase-associated lipocalin (NGAL) and cystatin C (CysC) for acute kidney injury (AKI) diagnosis in critically ill children.

METHODS

Serum NGAL (sNGAL) and urinary NGAL (uNGAL) and CysC were measured daily in the first 48 h from pediatric intensive care unit admission in 11 consecutive critically ill children with severe sepsis; a single measurement was made in a population of 10 healthy controls undergoing minor ambulatory surgery to exclude possible biases in the laboratory methods.

RESULTS

uNGAL, serum CysC (sCysC), and urinary CysC (uCysC) levels were significantly increased in patients with septic AKI compared with septic patients without AKI, while sNGAL levels were not significantly different between septic patients with and without AKI. Median serum creatinine levels did not show significant differences between AKI and non-AKI patients.

CONCLUSIONS

uNGAL, sCysC and uCysC were not altered by sepsis and were good predictors of AKI. In a septic state, sNGAL alone did not discriminate patients with AKI from those without AKI.

Do interventions in an ICU affect the predictive ability of pediatric index of mortality and pediatric index of mortality-2 scores in a tertiary care hospital?

OBJECTIVE

Our objective was to evaluate the effect of interventions in the initial period of stabilization (i.e., at 4 hrs) on the predictive ability of Pediatric Index of Mortality and Pediatric Index of Mortality-2 scores and to evaluate their performance in our ICU.

DESIGN

Prospective observational study.

SETTING

PICU of a tertiary care teaching hospital.

PATIENTS

Consecutive children aged 2 months to 17 yr admitted to our ICU from June 2010 to July 2011 were included.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We prospectively recorded the baseline characteristics, variables of Pediatric Index of Mortality and Pediatric Index of Mortality-2 at 1 and 4 hrs after admission, and the outcome data in a predesigned proforma. We compared the performance of the scores at these two time points by calculating their discriminative ability and calibration as measured by the area under curve of the receiver operating characteristic curves and the Hosmer-Lemeshow goodness-of-fit test, respectively.Of the 282 children enrolled, 93 (32.9%) died. The median (interquartile) age of the study patients was 3.5 yr (0.8, 10). The major reasons for ICU admission as well as mortality were sepsis/severe sepsis and cardiac and neurological illnesses. The area under curves for Pediatric Index of Mortality at 4 and 1 hrs were 0.73 (95% confidence interval 0.66-0.79) and 0.70 (0.63-0.77), respectively. The corresponding values for Pediatric Index of Mortality-2 were 0.72 (0.66-0.79) and 0.71 (0.64-0.78), respectively. The goodness-of-fit test showed a good calibration across deciles of risk for the two scores at both the time points (p > 0.1 for all). The calibration across different age and diagnostic subgroups was also good.

CONCLUSION

Interventions in the first 4 hrs did not affect the predictive ability of Pediatric Index of Mortality and Pediatric Index of Mortality-2 scores. The 4-hr scores may be used in place of the 1-hr score, particularly in units where scoring is not possible with in the 1-hr time frame.

Validation of pediatric index of mortality 2 (PIM2) in a single pediatric intensive care unit in Japan

OBJECTIVE

The Pediatric Index of Mortality 2 (PIM2), one of the key mortality prediction models for children in intensive care units, has not been validated in Japan. The purpose of this study was to validate the performance of PIM2 in a population of patients admitted to one pediatric intensive care unit (PICU) in Japan.

METHODS

This was a prospective cohort study involving consecutive patients admitted to the largest multidisciplinary PICU in Japan between 1 January 2008 and 31 December 2010. There were no interventions.

RESULTS

A total of 2,536 patients were included in this study of whom 67 (2.6%) died. Discrimination between survival and death assessed by the area under the receiver operating characteristic curve was 0.92 [95% confidence interval (CI) 0.89-0.96]. Calibration across the five risk intervals according to the Hosmer-Lemeshow goodness-of-fit test showed a chi-square value of 4.8 (df = 5, p = 0.44). The standardized mortality ratio for the whole population was 0.77 (95% CI 0.59-0.96).

CONCLUSIONS

At the largest PICU center in Japan, the PIM2 was found to have excellent discriminatory power and good calibration, although it over-predicted deaths. Based on these results, PIM2 can be used as a good prediction model for pediatric mortality, which is a tool used to assess the overall quality of care in a PICU.

Lack of alphavbeta5 integrin receptor or its ligand MFG-E8: distinct effects on retinal function

BACKGROUND/AIMS

Diurnal phagocytosis of spent photoreceptor outer segment fragments by the retinal pigment epithelium (RPE) is critical for vision. We recently identified an important role for alphavbeta5 integrin receptors and their ligand Milk fat globule-EGF factor 8 (MFG-E8) in RPE phagocytosis.

METHODS

We compared RPE phagocytosis and retinal function between mice deficient in alphavbeta5 integrin receptors and mice deficient in the secreted integrin ligand MFG-E8.

RESULTS

Both beta5-/- and MFG-E8-/- mice exhibit the same phagocytic defect: RPE cells retain basal uptake activity but completely lack the burst of phagocytic activity as well as the rhythmic activation of Mer tyrosine kinase that follow circadian photoreceptor shedding in wild-type RPE. Strikingly, electroretinogram photoresponses decline with age only in beta5 -/- but not in MFG-E8-/- retina.

CONCLUSION

These results identify a critical role of alphavbeta5 integrin receptors and their ligand MFG-E8 in synchronizing retinal phagocytosis. Additionally, we show that lack of alphavbeta5 receptors and MFG-E8 ligand have distinct consequences for retinal function. These intriguing results suggest that loss of phagocytic rhythm is not solely responsible for the age-related blindness of beta5-/- mice.